HPV Vaccine Gardasil 9 for Boys

Gardasil 9 is a vaccine (immunization) that protects against human papillomavirus (HPV). HPV is a virus spread through sexual contact and consists of multiple strains or types. While some strains of HPV come and go without symptoms, some can cause cancer while others can cause genital warts.

HPV vaccination prevents nine high-risk types of HPV linked to cancer, predominately cervical cancer but also cancer of the anus, vagina, vulva, penis, mouth, tonsils, and throat.

This article reviews why the vaccine is recommended for males and the vaccine schedule. It also covers the risks, safety, and effectiveness of the vaccine.

Teenage boy (12-13) bracing himself for injection
FangXiaNuo / Getty Images

When the original Gardasil was first approved by the U.S. Food and Drug Administration (FDA) in 2006, it was recommended for girls and women ages 9 to 26 only. It was only in 2011 that the Centers for Disease Control and Prevention (CDC) said the vaccine should be given to boys and men 9 to 26.

In 2018, the CDC further expanded its recommendation so that men and women ages 27 to 45 can opt for HPV vaccination after consultation with a healthcare provider.

Gardasil 9 is today the only HPV vaccine approved for use in the United States following the voluntary discontinuation of Cervarix (which protected against two HPV types) in 2016.


The FDA and CDC decided to extend the use of Gardasil to boys based on studies that showed that HPV increases the risk of anal cancer by 17- to 20-fold in men and women and that the risk in men who have sex with men (MSM) may be increased by as much as 70-fold.

What's more, the virus is spread through sexual contact, which means that a male who is infected with HPV can pass it to another male or female. By preemptively vaccinating boys before they are sexually active, the spread of infection can be reduced along with a boy's risk of anal, penile, and oropharyngeal (mouth and throat) cancer in later life.

Gardasil 9 protects against seven high-risk types of HPV associated with cancer (types 16, 18, 31, 33, 45, 52, and 58) and two low-risk types associated with genital warts (types 6 and 11).

HPV Infection in Males

According to the CDC, an estimated 79 million people in the United States are infected with HPV. There are over 200 types of HPV, 40 or so of which are sexually transmitted. The majority do not cause cancer, and some cause no symptoms at all.

Genital Warts

A handful of low-risk HPV types are responsible for genital warts, of which 90% are linked to HPV types 6 and 11. In males, warts may occur on the penis, scrotum, testicles, anus, groin, or thighs.

In most cases, genital warts pose no major health risks, although they may be unsightly and embarrassing. Some will resolve on their own; others may require medical treatment to remove them (although recurrence is common).


However, the types of HPV that can cause genital warts are not the same as those that can cause cancer. Most people who become infected with these do not know that they have been infected.

These high-risk types, called oncogenic HPV, can linger and cause normal cells to turn cancerous—although it is not entirely clear why. While the type of HPV plays a large role in this, so can co-occurring conditions like HIV, which is already linked to an increased risk of many types of cancer.

Moreover, over 30% of penile cancers are linked to two specific HPV types, type 16 and type 18. These are two types targeted by Gardasil 9 and the ones linked to most cervical cancers, anal cancers, and other HPV-associated cancers. Of the 20,000 new anal cancer cases each year (worldwide), an estimated 90% were caused by HPV.

In men with HPV and HIV, the incidence of anal cancer is roughly 78 per 100,000 compared to only 2 per 100,000 in the general population. Some studies have suggested that the rate may be as high as 168 per 100,000.

Immunization Schedule

The CDC recommendations for HPV vaccination are the same for boys and girls. The ideal age to receive Gardasil 9 is between 11 and 12, when most people are not yet sexually active.

American Cancer Society (ACS) Recommendations

The American Cancer Society (ACS) has lowered the recommended age to begin the vaccine to nine years old. It is safe at this age, long lasting, and effective. The goal of this recommendation is to ensure that children are getting this vaccination well in advance of initial sexual contact.

Anyone through the age of 26 should also be vaccinated if they have not previously done so or have not completed the recommended series.

Even so, vaccination during the preteen years is preferred as people are less likely to have been exposed to the virus and generally have a better immune response to the vaccine.

HPV vaccination is highly effective in people who have not been exposed to the HPV types that Gardasil 9 protects against.

The recommended dosage of Gardasil 9 varies by age.

Age Doses Schedule
9 to 14 years 2 •First dose between 11 and 12
•Second dose 6 to 12 months after first dose
15 to 45 years 3 •Second dose 1 to 2 months after first dose
•Third dose 6 months after first dose

It is important to note that while the FDA approved HPV vaccination in people ages 27 to 45, the CDC recommends "shared clinical decision-making" regarding HPV vaccination in this age group.

This is because is benefits of vaccination may be low given that the majority of people will have already gotten HPV by the time they are 27. By discussing your medical and sexual history with your healthcare provider, you can decide whether HPV vaccination is appropriate.

According to the CDC, HPV is so common that nearly all sexually active men and women will get the virus at some point in their lives.


Gardasil 9 should not be used by anyone who:

  • Has had a hypersensitive reaction to a prior dose of the vaccine
  • Has a history of an immediate hypersensitive reaction to yeast, as the vaccine is produced in Saccharomyces cerevisiae (baker's yeast)

Those with a latex allergy can safely take Gardasil 9. While there is a formulation that contains latex, it is no longer used in the United States.

While there is no evidence that the vaccine will negatively affect pregnancy or harm an unborn baby, most providers will delay the vaccination until after pregnancy.

Side Effects

In clinical trials, Gardasil 9 was found to be safe and effective, although it may cause mild, transient side effects in some people, including:

  • Pain, redness, or swelling at the injection site
  • Fever, usually mild
  • Nausea
  • Dizziness
  • Headaches
  • Muscle or joint pain


The HPV vaccine, Gardasil 9 protects against the human papillomavirus (HPV). HPV is a sexually transmitted infection (STI) with multiple strains. Some strains or types come and go on their own without ever causing symptoms. However, high risk strains can cause cancers and low-risk strains can cause genital warts. While HPV is not curable, it is treatable. 

The HPV vaccine is recommended for both male and females. The CDC recommends starting the vaccine around ages 11 or 12. The American Cancer Society (ACS) recommends starting at age nine to ensure the vaccine has been given before a person becomes sexually active.

A Word From Verywell

HPV is the most common sexually transmitted infection in the United States. While HPV will usually go away on its own, this shouldn't suggest you should take any chances with your child.

Unlike most vaccines recommended by the CDC, HPV vaccination is mandated by only a small handful of states. In fact, as of 2020, only Hawaii, Rhode Island, Virginia, Washington, D.C., and Puerto Rico required HPV vaccination in school children.

It, therefore, leaves it up to you as a parent to get your child vaccinated if your state or school does include Gardasil 9 on its vaccine schedule.

Frequently Asked Questions

  • Are Gardasil shots effective?

    Yes, the cilnical trials used to gain approval for Gardasil 9 found it to be almost 100% effective in preventing the HPV strains that it targets. This is true if someone has not already contracted a strain before the vaccine. However, even if you have one strain, the vaccine can still prevent the other types.

  • Are all three HPV doses necessary?

    Only two doses are recommended for those who receive the vaccine before they turn 15. If the two doses were given less than five months apart, a third dose is recommended. Three doses is also recommended for those over 15 and for those with decreased immune systems who are between nine and 26.

18 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  12. Chaturvedi AK. Beyond cervical cancer: burden of other HPV-related cancers among men and women. J Adolesc Health. 2010;46(4 Suppl):S20-S26. doi:10.1016/j.jadohealth.2010.01.016

  13. Meites E, Szilagyi PG, Chesson HW, Unger ER, Romero JR, Markowitz LE. Human papillomavirus vaccination for adults: updated recommendations of the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 2019;68:698-702. doi:10.15585/mmwr.mm6832a3

  14. American Cancer Society. Prevent 6 cancers with the HPV vaccine.

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By Brandi Jones, MSN-ED RN-BC
Brandi is a nurse and the owner of Brandi Jones LLC. She specializes in health and wellness writing including blogs, articles, and education.

Originally written by Lisa Fayed